The invention concerns a lock device. A lock device of this type is disclosed by DE 199 44 070 C2. In that lock device, the coding of the key consists of a coding groove that extends in the longitudinal direction of the key. The corresponding tumblers have projections to serve as scanning points, and, when the key is inserted, each of these projections fits into a certain cross section of the coding groove. The position of the projection on the tumbler depends on the coding of the groove and thus constitutes the corresponding countercoding of the lock device.
EP 0 267 316 A1 describes a different lock device, in which the bit of the key has a polygonal cross section. Notches of different depths are formed on the edges of the bit. Spring-loaded tumbler pins engage the edges of the key bit and scan the depth of the notches in the corner regions of the key bit. At the tip of the key bit, bevels are provided on the lateral surfaces between the edges to raise the tumbler pins when the key is inserted.